Food Safety FAQ

Research on steam canners has found that food canned in them is not heated to a temperature as high as when the same food is canned in a boiling water bath canner. The lower temperature results in less killing power of the bacteria, under processing and considered a risk of spoilage. Therefore the use of steam canners for home canning is NOT recommended.

In addition to unsafe canning temperatures steam canners can cause steam burns to those using them, and increased steam burns.

Even if there are instructions for pressure canning in the manufacturer’s directions, we do not support the use of the USDA canning processes in the electric, multi-cooker appliances now containing “canning” or “steam canning” buttons on their front panels.  Our pressure process directions have not been developed for that type of appliance, and the canner being used does matter. Our recommendations were determined for stovetop pressure canners which hold four or more quart-size jars standing upright. 

All pressure canners, including ‘self-venting’ pressure canners, do need to be vented 10 minutes before the pressure is allowed to rise. This venting time is a way to be certain that all air is removed from the pressure canner.

Research has shown that under some conditions (particularly with the raw-packed foods) all air may not be removed from self-venting pressure canners. If there is air in the pressure canner, the temperature is much lower than if the canner contains only water and steam.

Vacuum packaging machines will extend the storage time of refrigerated food, dried foods, and frozen foods. However vacuum packing machines or sealers are NOT a substitute for heat processing of home canned foods.

Perishable foods packed in a vacuum package must be refrigerated or frozen. They cannot be safety stored at room temperature. The removal of most of the oxygen does not inhibit all growth of bacteria. Some bacteria that grow in a low-oxygen environment can cause food spoilage. These bacteria can cause serious illness or death in humans.

Per the Center for Food Safety:

“Freezing extends the shelf life of food as storing food at -18 ^oC can inactivate enzymes and microorganisms including bacteria, yeasts and molds in food. By freezing, the water in food turns into ice crystals and becomes unavailable to microorganisms that need it to grow. Parasites like Trichina can also be destroyed at freezing temperatures. However, freezing does not kill bacteria and viruses, and viruses like norovirus remain infectious even at freezing temperatures. Besides, any microorganisms present can also become active again when the food is defrosted.”

Per the National Center for Home Food Preservation:

“Freezing is one of the easiest, most convenient, and least time-consuming methods of preserving foods. Freezing does not sterilize foods; the extreme cold simply retards the growth of microorganisms and slows down chemical changes that affect quality or cause food to spoil.

This process involves reducing the temperature of the food product to a point where water within it solidifies into ice, creating an inhospitable environment for microbial activity. The key to successful freezing lies in achieving rapid and uniform cooling, minimizing the formation of ice crystals, which can negatively impact the texture and quality of the food. Understanding the science of freezing, including the principles of heat transfer and the kinetics of freezing, is essential for preserving the nutritional content and overall appeal of a wide range of foods, from vegetables and fruits to meats and dairy products.” 

Many years ago, storing eggs was important due to lack of refrigeration or other safe preserving methods. From this time came an egg storage method that is not recommended today due to advancements and knowledge of egg safety. One method that has become very popular is storing eggs in lime water, also called “water glassing.” This method is not considered safe, nor is it a recommended method to store eggs for the long term.

It depends…on the recipe. Most salsas are a mixture of low-acid foods (such as onions and peppers) with acid foods, such as tomatoes or fruits. Many tomatoes are near 4.6 pH, which means it is important that 1) you use a salsa recipe that has been properly researched and tested, and 2) you measure ingredients carefully to ensure the correct acidity level, and 3) the salsas be made as described, following the guidelines for type of canner: either pressure canner or boiling water canner. IMPORTANT: Do not can other salsa recipes unless they have been properly researched for safety. Those may be frozen or stored in the refrigerator instead.